Interpretive Summary: Flooding is an effective means of weed control in rice culture and naproanilide is a herbicide that can enhance weed control in rice under flood conditions. The efficacy of naproanilide and flooding has not been tested on hemp sesbania control in rice. This paper describes the effects on naproanilide and flooding on hemp sesbania control. The growth of hemp was suppressed by flooding, and the combination of naproanilide treatment with flooding resulted in control of hemp sesbania.

Technical Abstract:
Flooding (submergence) was an effective method to suppress the growth of hemp sesbania relative to rice. When combined with flooding, naproanilide effectively controlled hemp sesbania at the cotyledon, 1-leaf and 2-leaf stages of growth but not at the 3-leaf stage of growth. Water depth was also an important factor in naproanilide control of hemp sesbania such that at 10 cm of flood growth was reduced 95%. Rice was not affected by the singular or combined naproanilide and flood treatments.